Many portable electronics devices are adapted to receive power from a separate small power supply that is built directly onto a plug for inserting into an AC power main. The separate power supply may provide regulated DC power, or may only provide rectified AC for regulation within the portable device.
Computers commonly transfer data to and from various peripheral devices such as printers and scanners through signal cables commonly called input/output (I/O) cables. Common cable standards in the personal computer industry include serial I/O (RS-232), parallel I/O (sometimes called Centronics), and Small Computer Standard Interface (SCSI).
It is common for portable computer peripheral devices to have two separate connectors and two separate cables for data transfer and for power. There is a need to minimize the number of connectors and cables on a portable device to enable smaller, lighter, maneuverable devices.
FIG. 1 shows one prior art solution. A peripheral device 100 has a permanently affixed cable 102 that in turn is connected to a computer I/O connector 104. Connector 104 is connected to a computer 108. A separate power supply 106 is also electrically connected to the connector 104. The peripheral device 100 is powered by the power supply 106 through connector 104.
For peripheral devices such as cameras and hand-held scanners, an I/O cable such as an RS-232 cable is relatively stiff and would hinder freedom of movement. Therefore, cameras and scanners preferably operate independently using battery power and internal data storage. Then, after images are captured, the images may be sent to a computer, to a printer, to a mass memory device, or to a communications device such as a portable telephone. For extended use in an area where AC power is conveniently available, it may be preferable to operate the devices from external power. Alternatively, a power supply connection may be needed to charge internal batteries. In general, there is a need to make cameras and hand-held scanners small, light and maneuverable. Eliminating one connector and one cable from the peripheral device enables a smaller, lighter, more maneuverable peripheral device. There is a need for additional configuration flexibility for portable electronics devices that are battery powered but which may use a separate power supply when convenient or may use a separate power supply for recharging.